Air conditioning apparatus



Aug. 16, 1932. THOMPSON 1,872,195

AIR CONDITIONING APPARATUS Filed April 8. 1931 2 Sheets-Sheet 2 19 A d [725/6735? 18 W Patented Aug. 16, 1932 PATENT OFFICE DELL THOMPSON, O1! DETROIT, MICHIGAN, ABSIGNOR 1'0 DRYING SYSTEMS, INC., 01' OHIOAGO, ILLINOIS, A CORPORATION OF ILLINOIS m CONDITIONING APYABA'I'US Application fled April 8,

This invention relates to the circulation of air and its conditioning with reference to temperature and humidity for interior heatin purposes, including air conditioning for 5 in ustrial operations, for example, the conditioning of air for bakers proof rooms.

The objects of the invention are to provide a unitary compact apparatus capable of exactLy maintaining a given air temperature and'humidity condition of the air, and which may be set for operation within a comparatively wide range with reference to temperature and relative humidity.

The objects of the invention are accomplished by a construction as illustrated in the drawings wherein:

Figure 1 is a plan view of the air conditioning apparatus with its top plate and removable covers partly broken away to show the arrangement of the interior thereof.

Fig. 2 is a side view of the air conditioning apparatus.

ig. 3 is a longitudinal sectional view taken on the line 3-3 of Fig. 1. V

Fig. 4 is an end view looking from the left of Figs. 1, 2 and 3.

. Fig. 5 is a plan view of reticulated metal sheets which are employed in the humidifying or air scrubbing element of the apparatus.

Fig. 6 is an enlarged fragmentary view of one of the sheets shown in Fig. 5.

In its general features this air conditioning apparatus consists of a cabinet of tank-hke constructionfor holding a supply of water at the bottom thereof, and above the water line, inrseries, are air humidifying and air heating elements; at one end the cabinet supports a motor-driven blower for circulating air through the apparatus, causing it to pass through the humidifying and heating elements thereof. Water is continuously circulated from thebott om of the tank to the top of the humidifying element, and works downwardly through this element to a trough at the bottom thereof, from which it spills back into the tank.

The temperature of the water at the bottom of the humidifying element is utilized to control a thermostatic steam valve. The rate of steam flow through this valve deter- 1931. fierlal No. 528,490.

colates downwar ly through a maze o horizontal superposed reticulated metal sheets.

The arrangement of these sheets is such that they alternate with reference to the arrangement of perforations therein, in such manner as to provide a vast number of small irregular passageways for air which is drawn through the humidifier. The air comes in contact with a large area of wet, uneven metallic surfaces in the humidifier, where it absorbs the required moisture according to the rate of flow of water through the humidifier and the temperature of the air passing thereover.

The air passes from the humidifier into a heater which is preferably of the finned copper tube radiator type, and receives steam at its upper header at a rate which is regulated by a thermostat in the air receiving end of the apparatus, and which controls a steam valve in the steam conduit leading to the rad ator. From the bottom header of the radlator condensate is discharged through a steam trap into the water at the bottom of the tank. Thus, while the steam which is used in both the humidifier and the heater or radiator imparts its heat to the water and the air, none of it escapes into the air as it is condensed by contact with the water. The humidifier serves the purpose of collecting any dust which may be in the air, causing it to be washed downwardly where it may settle in a trough below the humidifier or at the bottom of the tank. Occasional cleaning of the apparatus is effected by draining it and washing it out with water from a hose nozzle.

The reticulated metal sheets which provide the air and water contacting surfaces of the humidifier are formed by slitting metal sheets and expanding the sheets to provide preferably diamond-shaped openings therein. The sheets are arranged so that the long axes of these openings alternate in directionthat is, extend longitudinally in one sheet and transversely in the sheet next above or below. In forming the openings, the metal is bent into somewhat flat, irregular, inclined strands. The sheets are in contact with each. other, and the air striking the many inclined surfaces thereof is alternately pro ected upwardly and downwardly as it passes through the humidifier and is cut into a vast number of minute streams.

Referring to the drawings, the cabinet 1 provides an enclosure with an air opening at 2 and an air outlet 3 through the flanged end 4 of the blower unit 5, which is mounted in the right hand end of the cabinet. Removable cover plates 6 and 7 are provided at the top of the cabinet for cleaning purposes and to permit the mounting therein of the humidifying unit 8, heater 9 and the blower 5.

The inlet to the blower is indicated at 10, its impeller at 11, and the motor therefor at 12 mounted upon a support 13 'secured to the right hand end of the cabinet.

The bottom end of cabinet 1 forms a water tank and water is admitted thereto to the level indicated, through the conduit 14 controlled by valve 15. The water level is maintained during the operation of the apparatus by the condensate delivered thereto from the humidifier and the heater. Excess water is drained through the overflow 16, and the tank may be completely drained at times of cleaning thereof through the drain pipe 17 under the control valve 18. The overflow 16 and the drain 17 communicate with the same discharge conduit 19.

Steam is delivered to the apparatus through the supply conduit 20, Fig. 3, from which branches 21 and 22 respectively, conduct the steam to an ejector 23, and to the radiator 9. Manually controlled shut-off valves 24 and 25 are provided in conduits 21 and 22 in advance of the automatic humidity and temperature controlling valves 26 and 27. Each of these automatic valves may be set for a predetermined humidity and temperature condition by means of adjustable handles 26' and 27. When these handles are once set for a given performance they are left in their set position, variation of the flow of steam being then further regulated by the operation of tubular thermostatic devices 28 and 29.

The latter, and the valves operated thereby, are not illustrated in detail as they are well known constructions and are enerally operated by the expansion of a fluid in the tubes 28 and 29, the motion being transmitted to valve adjusting diaphragms in the viilves 26 and 27 through the conduits 30 and 3 The humidifying element 8 consists of an open frame supported in the side walls of the cabinet at 32, including side plates 33,

between which the reticulated metal sheets 34 extend. The side plates are flanged over the edges of the sheets 34 to prevent the passage of air around the sides of the humidifier; likewise the space between the top of the cabinet and the stack of sheets 34 is closed by plates 35.

Secured to the bottom of the humidifier is a V-shaped trough 36 which extends downwardly below the water level in the cabinet 1 and thus prevents the passage of air around the bottom of the humidifier. The trough also serves to collect water which percolates downwardly through the humidifier, and subjects the thermostatic tube 29 to the temperature of this water. \Vater spills from the trough 36 over the front edge thereof.

Above the stack of sheets 34 is a perforated metal water distributing plate 37 be tween the side walls of the cabinet and the vertical plates 35. \Vater is delivered to this plate at the desired rate from a horizontally extending perforated tube 38 which communicates with a vertical conduit 39 on the outside of the cabinet, at the lower end of which is located the ejector 23 communicating with a steam conduit 40 under the control of automatic valve 26.

The water inlet to the ejector is indicated at 41, Fig. 2, and consists of a tube extending through the side wall of a tank and terminating in the inlet nozzle 42, Figs. 3 and 4. The ejector serves continuously to lift water from the bottom of cabinet 1 to the perforated tube 38 at a rate controlled by the valve 26 which admits steam to the ejector and is under the control of the thermostatic element 28.

The ejector is designed, in the manner hereinafter set forth, for operation with low steam pressures, and the water inlet thereto is provided with a check valve 45, as indicated in Fig. 4. This check valve, in case of extremely low steam pressures, prevents steam from backing into the water and thus whatever steam passes through the. ejector upon such low pressures travels upwardly and is delivered with whatever wateris in the conduit 39 to the element 8 and prevents the latter from becoming dry and the humidity control ceasing to function from lack of cooling by evaporation or lowering of temperature in the V-trough 36 under circumstances when dry air enters the cabinet. To make the ordinary ejector of commerce, for instance the Penberthy ejector, operable with as low as one pound steam pressure, I proceed as follows:

1. Enlarge steam jet to about twice its original diameter.

2. Increase by about 25 per cent the distance between the steam jet and the delivery jet by reducing the length of the steam jet accordingly.

3. Close the two openings in the side of the delivery jet.

The set of plates 34 alternate with reference to the lon axes of the diamond-she. ed perforations t erein, as illustrated by ig. 5, and the inclined connecting portions thereof 43 surrounding the diamond-shaped apertures serve to direct the water from side to side as it passes downwardly through the plates, and likewise serve to break up the air current passing at right angles to the direction of the flow of the water, thus brin ing the air into intimate contact with the arge area of wet surface.

The rate at which the air takes up humidity is dependent both upon the rate of flow of Water through the humidifier under the control of thermostat 28, and the temperature of the air which is under the control of thermostat 29, it being understood that the air is to a great extent continuously recirculated through the apparatus.

The heater 9 consists of steam headers 44 and 45, connected together by finned copper radiator tubes 46. The header 44 receives steam through the fitting 47 communicating with valve 27 under the control of thermostat 29. The condensate and. steam which pass through the air heater are delivered from header 45 to the water in the bottom of cabinet 1 through steam trap 48.

In the operation of the air conditioning apparatus, air is drawn therethrough by blower 11 enterin at inlet opening 2 and discharging from t e blower at 3. The entering air controls the operation of the thermostat 29, which, through the valve 27, regulates the delivery of steam to the heater 9. The condensate from this heater is delivered to the water in cabinet 1 from the steam trap 48. The air is continuously recirculated in this manner, its fall in temperature during use being compensated for by the action of heater 9. Thus, the temperature of delivery of the air by the blower 5 is maintained constant.

Provision may be made in the ductwork connecting the apparatus with the proof room, or the like, for admitting a predeter- ,mined amount of fresh air and discharging a corresponding amount of used air.

The humidity of the air is maintained constant by the humidifier 8, the rate of delivery of water to the humidifier being under the control of valve 26, the-action of which is regulated by thermostat 28. Both the valves 26 and 27 are manually set for the desired humidity and temperature conditions by manually adjustable members 26' and 27 thereof. The thermostat 28 is subject to the temperature of the water in trough 36, after the water has passed through the humidifier 8 and before it flows into the bottom of cabinet 1.

Although butone specific embodiment of this invention has been herein shown and demostat located in said trough, means scribed, it will be understood that certain details ofthe construction shown may be altered or omitted without departing from the spirit of this invention as defined by the following claims:

I claim:

1. An air conditioning apparatus comprising a cabinet, means for maintaining a water level therein, an air inlet and an air outlet in said cabinet above said water level, means for forcing air through the cabinet, a humidifying device located in the path of travel of the air through the cabinet and having at its lower end a trough extending above and below the water level in the cabinet, a thferpumping water from the bottom of the cabi net to the top of said humidifier, said means for pumping'water being under the control of said thermostat.

2. An air conditioning apparatus comprising a cabinet, means for maintaining a water level therein, an air inlet and an air outlet in said cabinet above said water level, means for forcing air through the cabinet, a humidifying device located in the path of travel of the air through the cabinet and having at its lower end a trough extending above and below the water level in the cabinet, 3. thermostat'located in said trough, a steam ejector for pumpin water from the bottom of the cabinet to t e top of said humidifier, and means under the control of said thermostat for regulating the delivery of steam to said injector.

3. An air conditioning apparatus comprising a cabinet, means for maintaining a water level in the lower portion thereof, a humidifier located above the water and in the cabinet an air inlet and outlet in said cabinet, and a blower arranged for forcing air through said humidifier, said humidifier comprising a stack of slit and expanded metal sheets, said sheets being arranged so that the openings therein extend at right angles, to each other in alternate sheets and means for drawing water from the lower portion of said cabinet and causing the Water to flow over the surfaces of said sheets.

4. An air conditioning apparatus comprising a cabinet. means for maintaining a water level in the lower portion thereof, a humid ifier located above the water and in the cabinet, an air inlet and outlet in said cabinet, a blower arranged for forcing air through said humidifier, said humidifier comprising a stack of slit and expanded metal sheets, said sheets being arranged so that the openings therein extend at right angles to each other in alternate sheets, a trough at the bottom of said humidifier for collecting water.

passing through the humidifier, means for pumping water from the bottom of the cabinet to the top of the humidifier, and a thermostat in said trough arranged to control said means for pumping the water.

5. An air conditioning apparatus comprising a cabinet, means for maintaining a water level therein, an air inlet and an air outlet in said cabinet above said water level, means for forcing air through the cabinet, a humidifying device located in the path of travel of the air through the cabinet and having at its lower end a trough extending above and below the water level in the cabinet, a thermostat located in said trough, means for pumping water from the bottom of the cabinet to the top of said humidifier, said means for pumping water being under the control of said thermostat, a steam radiator Within the cabinet having an outlet beneath the water level in the cabinet.

6. An air conditioning apparatus compris ing a cabinet, means for maintaining a water level therein, an air inlet and an air outlet in said cabinet above said water level, means for forcing air through the cabinet, a humidifying device located in the path of travel of the air through the cabinet and having at its lower end a trough extending above and below the water level in the cabinet, a thermostat located in said trough, means for pumping water from the bottom of the cabinet to the top of said humidifier, said means for pumping water being under the control of said thermostat, a steam radiator within the cabinet having an outlet beneath the water level in the cabinet, and a thermostat for regulating the admission of steam to said radiator.

Signed at Chicago this 4th day of April,

DELL THOMPSON.

CERTIFICATE OF CORRECTION.

Patent No. l, 872, 195.

August 16, 1932.

DELL THOMPSON.

It is hereby certified that the above numbered patent was erroneously issued to "Drying Systems, Inc.," as assignee o f the entire interest in said invention,

whereas said patent should have been issued to the inventor said Thompson, and

Drying Systems, Inc., as assignee of one-hal ords of assignments in this office;

i interest only ,as shown by the recand that the said Letters Patentshould be read with this correction therein that the same may conform to the record of the case in the Patent Office.

Signed and sealed this 22nd day of November,

(Seal) M. J. Moore,

Acting Commissioner of Patents.

stat in said trough arranged to control said means for pumping the water.

5. An air conditioning apparatus comprising a cabinet, means for maintaining a water level therein, an air inlet and an air outlet in said cabinet above said water level, means for forcing air through the cabinet, a humidifying device located in the path of travel of the air through the cabinet and having at its lower end a trough extending above and below the water level in the cabinet, a thermostat located in said trough, means for pumping water from the bottom of the cabinet to the top of said humidifier, said means for pumping water being under the control of said thermostat, a steam radiator Within the cabinet having an outlet beneath the water level in the cabinet.

6. An air conditioning apparatus compris ing a cabinet, means for maintaining a water level therein, an air inlet and an air outlet in said cabinet above said water level, means for forcing air through the cabinet, a humidifying device located in the path of travel of the air through the cabinet and having at its lower end a trough extending above and below the water level in the cabinet, a thermostat located in said trough, means for pumping water from the bottom of the cabinet to the top of said humidifier, said means for pumping water being under the control of said thermostat, a steam radiator within the cabinet having an outlet beneath the water level in the cabinet, and a thermostat for regulating the admission of steam to said radiator.

Signed at Chicago this 4th day of April,

DELL THOMPSON.

CERTIFICATE OF CORRECTION.

Patent No. l, 872, 195.

August 16, 1932.

DELL THOMPSON.

It is hereby certified that the above numbered patent was erroneously issued to "Drying Systems, Inc.," as assignee o f the entire interest in said invention,

whereas said patent should have been issued to the inventor said Thompson, and

Drying Systems, Inc., as assignee of one-hal ords of assignments in this office;

i interest only ,as shown by the recand that the said Letters Patentshould be read with this correction therein that the same may conform to the record of the case in the Patent Office.

Signed and sealed this 22nd day of November,

(Seal) M. J. Moore,

Acting Commissioner of Patents. 

